Indirect water-heating apparatus



July 14, 1925. t 1,545,704

c. SMITH INDIRECT WATER HEATING APPARATUS Filed April 9, 1923 l'i'aa'emzbr: 672eZ'aroo'cZ fivzzi'h tively and a normally closed check valve 28 is placed in the branch connection 25. The check valves 26 and 27 are of similar construction and one of them is shown in detail in Fig. 2.

When no water is being withdrawn from the storage tank 21, the water will circulate in its normal path from the coil 12 through the riser to the top of the tank 21 and from the bottom of the tank 21 through the pipe 24: and the feed pipe'23 back of the coil 12. The check valve 28 remains closed and the flow of water is not suiliciently active to close the check valve 26.

If, however, water is withdrawn from the tank 21 through the pipe 22, a much more rapid inflow of water occurs in the pipe 23. The pressure of this inrushing cold Water upward in the pipe 24 raises the valve 27 thus closing the pipe 24 andpreventing direct introduction of cold water intorthe tank 21. Similarly the rapid upward flow of water to the riser 20 closes the check valve 26 and prevents discharge thereof to the top of the tank '21.

The incoming cold water is thus forced to pass through the heating coil 12 and to enter the tank 21 through the branch con nection 25 by opening the check valve 28. In this way the cold water is partially heated by passing through the coil 12 and isdelivered to the lowest and coolest part of the tank 21, leaving the relatively hot water in the top of the tank substantially nndis-.

turbed. As soon as the feed of cold water oeases,the.check valvesv 26and 27 open and the check valve 28 closes, and the normal circulation of water through the pipes 20 and 24 is resumed. Water may thus be drawn from the storage tank 21 without greatly reducing the temperature of the water remaining in the tank by the direct mixture of cold water therewith in the hotter portions thereof.

If the inflow of feed water is too slight to raise the check valve 26 the feed water.

may enter the top of the tank 21 through the riser 20, but in such small amount that it is not objectionable. Thetemperatureof this small amount of wateris also materially raised in passing throughthe indirect heater 11. V

Having thus described the several features of my invention and the advantages thereof, I do not wish to be limited to the details. herein disclosed otherwise than as set forth in the claims but what I claim is 1. Means for heating water indirectly having, in combination, a main water heater, an indirect heating apparatus comprising an indirect heater and upper and lower connections for the circulating heating water between said main heater and said indirect heater, said upper connection entering said main heater above the normal ing water in said indirect heating'apparatus, said latter means comprising a discharge outlet 'forsaid indirect heating apparatus, a valve toclose said outlet, and a second valve between said first valve and the lower pointof connection to said main heater.

3. Means for heating water indirectly having, in combination, a main'water heater, an indirect heating apparatuscomprising an indirect heater and upper and lower connections for the circulating heating water between said main heater and said indirect heater, said upper connection entering said main heater above the normal water level therein and extending below said normal water level within the heater, and means to start the circulation of heating water in said indirectheating apparatus, said latter means comprising a discharge pipe attached to said lower connection, a valve for said pipe, and a second valve in said lower connection between said first valve and said main water heater.

4. Indirect water heating apparatus comprising a storage tank, an indirect heater having a conduit therein for the water to be heated, a supply pipe for feed water under pressure and connections between saidcon duit, said tank and said supply pipe provi'ding a normal path of delivery of heated water from said conduit to the upper part of-said storage tank, and providing a second path of delivery from: said conduit to the lowerpart of said storage tank when cold feed water is admitted from said supply pipe to said apparatus.

5. Indirect water heating apparatus comprising a storage tank, an indirect heater having a conduit therein for the water to be heated, a supply pipe for feed water under pressure and connections between said conduit, said tank and said supply pipe providing a normal path-of delivery of heated water from said conduit to the upper part of said storage tank, and providing a second path of delivery from said conduit to the lower part of said storage tank when cold feed Water is admitted from said supply pipe to said apparatus, said feed water passing through said conduit before entering said storage tank.

6. Indirect water heating apparatus co1nprising a storage tank, an indirect heater having a conduit therein for the water to be heated, a supply pipefor feed water under pressure and connections between said conduit, said tank and said supply pipe providing a normalpath of delivery of heated water from said conduit to the upper part of said storage tank, said connections also including a branch passage from said conduit to the lower part of said storage tank providing a path ofdelivery for feed Water admitted to said apparatus from said supply pipe, and a return connection from said storage tank to said conduit, having means therein to prevent a flow of feed Water through said return connection direct to saidstorage tank.

said feed pipe to the lower part of said storage tank, a second branch connection storage tank, normally open check valves in said first branch connection and said riser, and a normally closed check valve in said second branch connection, said normally open valves being closed by a rush of feed water into said riser or said first branch connection. v

In testimony whereof I have hereunto affixed my signature.

CHETVVOOD SMITH;

from said riser to the lower part of said 

